PLano convex lens


#1

I want to print a plano convex lens with a 6mm diameter and focal length of 25mm. Does anyone know where I could either get and .stl or find dimensions to make this lens.they are awfully expensive to buy.I want to use it to collimate an LED so it doesnt need to be perfect.

Carl


#3

I looked but no one has one.If I could just get the specs of the lens I could do it myself.I ordered a lens and I may try reverse engineering one from that.I did the lens project of the formlabs site a while back and made a pretty nice magnifying lens so I know I could get a clear enough lens-I just need the shape of the lens


#4

OK I got a formula.All I need now is the refractive index of formlabs clear resin.Is there a spec on this anywhere?

Carl


#5

The safety datasheet suggests that clear, when cured is a polymethacrylate. Then the refractive index of perspex i.e. 1.49 would be reasonable value.


#6

Thank you HansSpaan.I did find a post on the forum from the Formlabs team saying they think it is around 1.5. Now I know the curvature radius and can try making a lens.

Carl